Algae Biotechnology – Green Cell-Factories on the Rise

Background: Recent years have witnessed fast growing developments in algae biotechnology. There is a broad range of diversity in algae biotechnology research and industry. Methods: A general literature review on all aspects of algae biotechnology was conducted. The main findings are summarized and the relevance for further research and biotechnological applications is discussed. Results: Algae are used as bioreactors for producing bioproducts such as pharmaceuticals, nutraceuticals, cosmetics, pigments and other useful chemicals, algal-based biomaterials, feed and more. Light-sensitive proteins from algae represent a cornerstone in the emerging field of optogenetics. In addition, many efforts are currently being undertaken to make algae competitive for production of bioenergy and biofuels, aiming to evolve into integrated biorefineries. Applied research approaches require mass-culture strategies for algae including bioprocess engineering, fermentation, harvesting and downstream processing. Some algalbased strategies also meet the requirements for use in bioremediation, biodegradation or other environmental applications. A powerful driving force in algae biotechnology is the enticing option to use genetically improved organisms. Selectable marker genes, reporter genes, promoters, transformation techniques and other genetic tools and methods are already available for several few algae species and this molecular toolbox is becoming increasingly powerful. Quite a few algae genome sequencing projects are completed and others are in progress or planned facilitating genetic engineering. Transgenic algae promise a much broader field of application than unmodified organisms or breeds, e.g., through additionally acquired physiological capabilities and new biochemical reactions, and they open the door to improved algal bioproducts and molecular farming. Conclusion: Algae are an extremely diverse group of organisms and therefore provide a substantial reservoir of biomolecules, cellular functions and physiological characteristics. Insight into cellular and molecular mechanisms and the opportunity to use algae as green cell-factories have resulted in a constantly growing economic importance of algae technologies and products.